Insoluble powder, powder for restoring barrier function of skin, powder for preventing/mitigating skin chapping, and preparation containing the same for external use on skin

ABSTRACT

A first subject of the present invention is an insoluble powder characterized in that a zeta-potential is a negative value. It is preferable that barium sulfate is a main ingredient in the insoluble powder. It is preferable that an average primary particle diameter is 3 to 100 μm, and an aspect ratio is 3 to 250 in the insoluble powder. It is preferable that the insoluble powder is a metal-doped barium sulfate powder obtained by reacting a barium ion and a sulfate ion in the presence of a metal ion. It is preferable that the metal ion is one or more selected from the group consisting of a lithium ion, a sodium ion and a zinc ion in the insoluble powder. A second subject of the present invention is a skin barrier function recovering powder, or a skin roughening preventing and improving powder, which comprises the aforementioned powder. A third subject of the present invention is a skin external composition characterized in that a content of the aforementioned powder is 1 to 40% by weight.

RELATED APPLICATIONS

This application claims priority to the Japanese Patent Application Nos.2002-91530 filed on Mar. 28, 2002 and 2002-344179 filed on Nov. 27, 2002is hereby incorporated with reference for all purposes.

BACKGOUND OF THE INVENTION

1. Field of the Invention

This invention relates to an insoluble powder, in particular, skinbarrier function recovering effect and skin roughening preventing andimproving effect of the same powder.

2. Prior Art

The skin is anatomically divided to epidermis, derma, and subcutaneoustissue. And said epidermis is composed of basal layer, spinosum layer,granular layer and horny layer. The horny layer of the epidermis is verythin and the thickness is below 20 μm. Accordingly drying and skinroughness are easy to be caused by the external stimulation such asultraviolet rays, drying, air pollution, and microorganism, and internalfactors such as sebum excretion, sweat gland functions, epidermismetabolism, and aging. Hitherto it was carried out that amino acids,polysaccharides, lipids, natural polymeric compounds and so on havinghigh moisturizing effect and water retention effect are blended to skinexternal composition.

However, the skin external composition that blended a large quantity ofthese moisturizing agents tends to become sticky, so sometimes happenthe harmful effect on use.

On the other hand, it is considered that, if a solid not permeating intothe interior of a skin such as a powder can be used as an activeingredient for improving skin roughening, safety can be furtherenhanced.

The present invention was done in view of the previous problems, and anobject thereof is to provide an insoluble powder having excellent skinbarrier function recovering effect and skin roughening preventing andimproving effect, and a skin external composition containing the same.

SUMMARY OF THE INVENTION

In view of the aforementioned problems, the present inventorsintensively studied and, as a result, found that a specified insolublepowder has excellent skin barrier function recovering effect, and skinroughening preventing and improving effect, which resulted in completionof the present invention.

That is, a first subject of the present invention is an insoluble powdercharacterized in that a zeta-potential is a negative value.

The zeta-potential refers to a part involved in electrophoresisphenomenon among a contact potential difference generated when a liquidis contacted with a solid, and is suitably used for assessing thesurface charge state of a subject. A method of measuring thezeta-potential in the present invention is as follows:

A sample was dispersed in a Tris.HCl buffer of pH 7.5, treated byultrasonic and allowed to stand for 18 hours to obtain a supernatantliquid, which was used for measurement. The zeta-potential was measuredby using an electrophoresis light scattering photometer LEZA-600manufactured by Otsuka Electronics Co., Ltd. Measurement was performedthree times, and results were shown as an average value thereof.

It is preferable that barium sulfate is a main ingredient in theinsoluble powder.

It is preferable that an average primary particle diameter is 3 to 100μm, and an aspect ratio is 3 to 250 in the insoluble powder.

In addition, the aspect ratio expresses (average primary particlediameter)/(average thickness).

It is preferable that the insoluble powder is a metal-doped bariumsulfate powder obtained by reacting a barium ion with a sulfate ion inthe presence of a metal ion.

It is preferable that a mole ratio of the barium ion, the sulfate ion,and the metal ion is 1:0.5 to 2:0.001 to 10 in the insoluble powder.

It is preferable that the metal ion is one or more selected from thegroup consisting of a lithium ion, a sodium ion and a zinc ion in theinsoluble powder.

A second subject of the present invention is a skin barrier functionrecovering powder, or a skin roughening preventing and improving powder,which comprises the aforementioned powder.

A third subject of the present invention is a skin external compositioncharacterized in that a content of the aforementioned powder is 1 to 40%by weight.

The insoluble powder of the present invention can be used as a skinbarrier function recovering agent, and a skin roughening preventing andimproving agent.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view showing an electric double layer via an epidermis.

FIG. 2 is a view for illustrating a method of measuring skin barrierfunction recovering effect.

FIG. 3 is a view showing skin barrier recovering effect of the casewhere a skin barrier was destructed and, after a while, an insolublepowder was coated.

FIG. 4 is a view of comparison of epidermis proliferating propertyabnormality preventing effect.

FIG. 5 is a view showing skin barrier recovering effect of a skinexternal preparation in which each blending amount of an insolublepowder was blended therein.

FIG. 6 is a view showing skin barrier recovering effect afterapplication of each skin external preparation to a human.

FIG. 7 is a view for comparing skin barrier function recovering effectbetween barium sulfate doped with zinc, and barium sulfate not dopedwith a metal.

FIG. 8 is a view for comparing skin barrier function recovering effectbetween barium sulfate doped with sodium, and barium sulfate not dopedwith a metal.

FIG. 9 is a view for comparing skin barrier function recovering effectbetween barium sulfate doped with lithium, and barium sulfate not dopedwith a metal.

FIG. 10 is a view for comparing skin barrier function recovering effectbetween barium sulfate doped with calcium, and barium sulfate not dopedwith a metal.

FIG. 11 is a view for comparing skin barrier function recovering effectbetween barium sulfate doped with aluminum, and barium sulfate not dopedwith a metal.

FIG. 12 is a view for comparing skin barrier function recovering effectbetween barium sulfate doped with magnesium, and barium sulfate notdoped with a metal.

FIG. 13 is a view for comparing skin barrier function recovering effectbetween barium sulfate doped with iron, and barium sulfate not dopedwith a metal.

FIG. 14 is a view for comparing epidermis proliferating propertyabnormality preventing effect between barium sulfate doped with zinc,and barium sulfate doped with iron.

FIG. 15 is a view showing skin barrier recovering effect of theinsoluble powder of embodiment 1.

FIG. 16 is a view showing skin barrier recovering effect of theinsoluble powder of embodiment 2.

FIG. 17 is a view showing skin barrier recovering effect of theinsoluble powder of embodiment 3.

FIG. 18 is a view showing skin barrier recovering effect of theinsoluble powder of embodiment 4.

FIG. 19 is a view showing skin barrier recovering effect of theinsoluble powder of embodiment 5.

FIG. 20 is a view showing skin barrier recovering effect of theinsoluble powder of embodiment 6.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Preferable embodiments of the present invention will be explained below.

In a normal skin, a calcium ion is localized in a corneum and a dermis,but due to a skin barrier destruction, suitable localization of acalcium ion in a skin is disintegrated, and diffusion of an ion isgenerated.

The insoluble powder of the present invention is characterized in that azeta-potential is negative.

When an insoluble powder having a negative zeta-potential is coated on askin, chloride ion (Cl⁻) or the like as an anion is attracted to aninsoluble powder side. For this reason, calcium ion and magnesium ion(Ca²⁺, Mg²⁺) are localized in an upper layer part of epidermis, in sucha manner that those ions are attracted by an anion. That is, aninsoluble powder forms a layer of an ion (electric double layer) on askin (FIG. 1). By formation of an electric double layer via anepidermis, diffusion of a calcium ion and a magnesium ion is suppressed,and skin barrier destruction is recovered.

First Working Mode

A first working mode of the insoluble powder of the present invention isan insoluble powder having an average primary particle diameter of 3 to100 μm and an aspect ratio of 3 to 250.

When an average primary particle diameter is 3 μm or larger, and anaspect ratio is 3 or larger, since movement of electrons in a particleis difficult to occur, the electric double layer is stabilized andexcellent skin barrier recovering effect is obtained. On the other hand,when an average primary particle diameter exceeds 100 μm, or an aspectratio exceeds 250, usability is deteriorated in some cases when blendedin a skin external preparation, being not preferable.

A kind of the insoluble powder used in a first working mode is notparticularly limited as far as the aforementioned conditions aresatisfied, but examples include barium sulfate.

A barium sulfate powder of the present invention can be prepared by theconventional method such as a method of mixing a barium compoundsolution containing a barium ion and a sulfate compound solutioncontaining a sulfate ion. A reaction temperature is preferably 50 to100° C., most preferably 70 to 100° C.

Any barium compound is used as far as it produces a barium ion in asolvent such as water and alcohol, being not particularly limited. Forexample, barium hydroxide, barium chloride, barium sulfide, bariumnitrate, barium acetate and so on are listed. Above all barium chlorideand barium hydroxide are desirable, because dispose of the by-product iseasy.

Any sulfuric compound is used as far as it produces a sulfuric ion in asolvent such as water and alcohol, being not particularly limited. Forexample, sulfuric acid, sodium sulfate, sodium hydrogensulfate, ammoniumsulfate, potassium sulfate, lithium sulfate and so on are listed. Aboveall sulfuric acid, sodium sulfate, and ammonium sulfate are desirable.

The barium compound and the sulfate compound are used in the state wherethey are dissolved in a solvent such as water and alcohol. Theconcentrations of the barium compound and the sulfate compound arepreferably 0.001 to 0.1 mol/L. When the concentration is lower than0.001 mol/L, efficacy is deteriorated in an industrial process and, whenthe concentration is higher than 0.1 mol/L, supersaturation occurs, anda number of fine particles are produced, that causes aggregation.

In the first working mode of the present invention, it is preferablethat a mole ratio of a barium ion and a sulfate ion is 1:0.5 to 2. Whena mole ratio of a sulfate ion is smaller than 0.5, or exceeds 2 relativeto a barium ion, efficacy is deteriorated in an industrial process.

Second Working Mode

A second working mode of the insoluble powder of the present inventionis a powder of barium sulfate doped with a metal. Barium sulfate dopedwith a metal has higher skin barrier function recovering effect ascompared with non-doped barium sulfate.

A powder of barium sulfate doped with a metal can be prepared byreacting a barium ion with a sulfate ion in the presence of a metal ion.For example, the powder can be prepared by a process of mixing (A) abarium compound solution containing a barium ion and (B) a metal saltcompound solution containing a metal ion and, thereafter, adding themixture to (C) a sulfate compound solution containing a sulfate ion, ora method of adding (A) a barium compound solution containing barium ionand (C) a sulfate compound solution containing sulfate ion to (B) ametal salt compound solution containing a metal ion. A reactiontemperature is preferably 50 to 100° C., most preferably 70 to 100° C.

As the barium compound, the sulfate compound, the barium solution, andthe sulfate solution, those described in the first embodiment aresuitably used.

Examples of a preferable metal ion for doping in the present inventioninclude zinc ion, sodium ion and lithium ion. These can be used alone,or by combining two or more of them. Each metal ion is given as asolution of a metal salt compound in water or alcohol.

As lithium salts, lithium hydroxide, lithium chloride, lithium nitrate,lithium carbonate, lithium acetate, and so on are used.

As sodium salts, sodium hydroxide, sodium chloride, sodium nitrate,sodium carbonate, sodium acetate, and so on are used.

As zinc salts, zinc hydroxide, zinc chloride, zinc nitrate, zinccarbonate, zinc acetate, and so on are used.

In the second embodiment of the present invention, it is preferable thata mole ratio of barium ion, sulfate ion and metal ion is 1:0.5 to2:0.001 to 10. When a mole ratio of metal ion is smaller than 0.001relative to barium ion, the effect of the present invention is notsufficiently exerted and, when the ratio exceeds 10, a produced powderof barium sulfate causes aggregation. In addition, when a mole ratio ofa sulfate ion is smaller than 0.5, or exceeds 2 relative to barium ion,efficacy is deteriorated in an industrial process.

The insoluble powder of the present invention can be used as a skinbarrier function recovering powder, or a skin roughening preventing andimproving powder.

When the insoluble powder of the present invention is blended in a skinexternal preparation, it is preferable that the insoluble powder iscontained at 1 to 40% by weight, particularly 8 to 40% by weightrelative to a total amount of a skin external preparation. When theamount is smaller than 1% by weight, the effect of the present inventionis not sufficiently exerted and, when the amount exceeds 40% by weight,formulation into a preparation becomes difficult.

In addition to the aforementioned essential ingredients, if necessary,additional ingredients which are conventionally used in a cosmeticand/or dermatological region can be appropriately blended in the skinexternal preparation of the present invention. For example, the skinexternal preparation may contain, anionic surfactant such as fatty acidsoap, alkyl sulfate ester salt, polyoxyethylene alkylether sulfate salt,acyl-N-methyltaurine salt, alkylether phosphate ester salt, N-acyl aminoacid salt, organic acid monoglyceride and so on; cationic surfactantsuch as alkyltrimethylammonium chloride, dialkyldimethylammoniumchloride, benzalkonium chloride, alkylpyridinium chloride and so on;ampholytic surfactant such as alkylamidodimethylaminoacetic acidbetaine, 2-alkyl-N-carboxy-N-hydroxyimidazolinium betaine, lecithin,enzymatic hydrolysis lecithin and so on; nonionic surfactant such asalkylpolyoxyethylene type, polyhydric alcohol ester type, alkylpolyglucoside type, alkyl polyglycerol type, sugar ester type,polyethylene oxide polypropylene oxide copolymer type, sorbitan fattyacid ester, dimethicone copolyol and so on; moisturizing agent such asglycerin, propylene glycol, 1,3-butylene glycol, polyethylene glycol,sorbitol, sodium lactate, sodium 2-pyrrolidone-5-carboxylate, and sodiumhyaluronate; synthetic polymer such as carboxyvinyl polymer, andpolyvinyl pyrrolidone; semisynthetic polymer such ascarboxymethylcellulose, and hydroxy propyl cellulose; natural polymersuch as xanthan gum, dextran, hyaluronic acid, casein, and collagen;ultraviolet absorber such as high molecular weight silicone,benzophenone derivative, p-aminobenzoic acid derivative, methoxycinnamonacid derivative; antioxidant such as tocopherol, BHT; sequestering agentsuch as EDTA, citric acid, hexametaphosphoric acid, pyrosulfurous acid;minute emulsion such as silicone micro emulsion, high pressureemulsified micro emulsion; and alcohol.

Furthermore as active substances, for example, whitening agent such asarbutin, ascorbic acid and its derivatives; anti-aging agent such asretinol and its derivatives; alpha-hydroxy acids such as lactic acid,and glycolic acid; hair growing agents; vitamins; antiinflammatoryagents; germicides; various salts and so on can be included.

Further, its use form is also arbitrary, and in addition to skin lotion,cream, emulsion, lotion, pack, ointment, mousse and soup, makeupcosmetics such as foundation, eye shadow, stain and black ring covering,lip cream, mascara, lipstick, body makeup product, hair rinse, shampoo,skin anti-sunburn cream, and sunburn cream can be used and, further, anyforms such as dermatological ointment and bath medicine may be used asfar as they are previously used in a cosmetic and/or dermatologicalregion.

In the following, the present invention will be explained by usingspecific examples. However, the present invention should not berestricted thereto. Unless otherwise stated, quantities are expressed aspercent by weight.

First, in order to investigate the insoluble powders in Table 1 for skinbarrier function recovering effect, the following experiment wasperformed.

Method of Measuring Skin Barrier Function Recovery Rate

1. A transdermal evaporating water level (TEWL) on a hairless mouse backwas measured with a water evaporation level measuring apparatus (Meeco).This value is defined as recovery rate of TEWL 100%.

2. Skin barrier destruction treatment was carried out by of peeling offan epidermis corneal layer of the whole back of a hairless mouse with acellophane tape until a TEWL value became 800 to 900 (8 to 9mg/cm²/hour). A value obtained by subtracting a TEWL value beforepeeling from a TEWL value immediately after peeling of an epidermiscorneal layer is defined as recovery rate of TEWL 0%.

3. 20 mg of each powder in the following Table 1 was suspended in 100 to200 μL of ion-exchanged water to prepare a suspension. The suspensionwas added dropwise to a 2 cm square of a filter placed on a plastic wrapto wet it. This was applied to a back of a hairless mouse immediatelyafter the aforementioned skin barrier destruction treatment so that theadded dropwise surface was contacted with the back, and was peeled offafter 10 minutes (FIG. 2). In addition, as a control, a filter wettedwith an ion-exchanged water was applied to other place on a back of thehairless mouse, and was peeled off after 10 minutes.

4. TEWL on a back of the hairless mouse was measured immediately afterpeeling (after 0 hour), and after 2, 4 and 6 hours based on a time atwhich the filter was peeled, and each recovery rate was calculatedaccording to the following equation.${{Recovery}\quad{{rate}(\%)}} = {100 \times \left\{ {1 - \left( \frac{\begin{matrix}{{{TEWL}\quad{every}\quad{hour}\quad{after}}\quad} \\{{comeal}\quad{layer}\quad{removal}}\end{matrix} - \begin{matrix}{{TEWL}\quad{before}} \\{{comeal}\quad{layer}\quad{removal}}\end{matrix}}{{\begin{matrix}{{TEWL}\quad{immediately}\quad{after}} \\{{comeal}\quad{layer}\quad{removal}}\end{matrix} - \begin{matrix}{{TEWL}\quad{before}} \\{{comeal}\quad{layer}\quad{removal}}\end{matrix}}\quad} \right)} \right\}}$

It can be said that as a recovery rate, in particular, a recovery rateat an early period is better, skin barrier function recovering effect ishigher.

Skin barrier function recovering effect is assessed by the followingcriteria.

Assessment Criteria

-   ◯: As compared with the case where ion-exchanged water was used, a    recovery rate after two hours is as high as 15% or higher, and a    recovery rate is superior also after 6 hours.-   Δ: As compared with the case where ion-exchanged water was used,    there is no difference in a recovery rate.

X: As compared with the case where ion-exchanged water was used, arecovery rate is inferior. TABLE 1 zeta- Insoluble potential RecoveryExample powder Shape (mV) effect 1 Barium sulfate plate-like state −3.69◯ 2 Lithium doped plate-like state −2.34 ◯ barium sulfate 3 Bariumsulfate undefined state 1.11 Δ 4 Iron doped fir-like state 0.59 X bariumsulfate 5 Aluminum doped plate-like state 3.08 Δ barium sulfate

A method of measuring the zeta-potential in the present invention is asfollows:

A sample was dispersed in a Tris.HCl buffer having of pH 7.5, treated byultrasonic and allowed to stand for 18 hours to obtain a supernatantliquid, which was used for measurement. The zeta-potential was measuredby using an electrophoresis light scattering photometer LEZA-600manufactured by Otsuka Electronics Co., Ltd. Measurement was performedthree times, and the results were shown as an average value thereof.

From Examples 1 and 2, it is seen that a powder having a plate-likeshape has higher skin barrier function recovering effect. In addition,from Examples 3 and 4, it is seen that a powder having an undefined orfir-like shape or the like other than plate-like shape has no recoveringeffect, or delays recovery. However, from Example 5, it is thought thatsince a powder having a plate-like shape has low recovering effect insome cases, a negative zeta-potential value is required in addition to ashape of plate-like.

Considering that barium sulfate is substantially insoluble in water, andthat the shape is necessary to be plate-like, it is necessary that apowder of the present invention is insoluble in an aqueous system.

The reason why skin barrier destruction is recovered by coating of aninsoluble powder having a plate-like shape and having the negativezeta-potential value, can be contemplated as follows:

When an insoluble powder having a negative zeta-potential is coated on askin, chloride ion (Cl⁻) or the like as an anion is attracted to aninsoluble powder side. For this reason, calcium ion and magnesium ion(Ca²⁺, Mg²⁺) are localized at an upper layer part of an epidermis insuch a manner that those ions are attracted by an anion. That is, aninsoluble powder forms a layer of ion (electric double layer) on a skin(FIG. 1). By formation of an electric double layer via an epidermis,diffusion of calcium ion and magnesium ion is suppressed, and skinbarrier destruction is recovered.

It is considered that, unless a shape of an insoluble powder isplate-like, its aggregate has many lattice defects and movement ofelectrons in a particle occurs and, since the electric double layer isunstable, skin barrier function recovering effect is low, while if ashape is plate-like, movement of electrons in a particle does not occur,and the powder has excellent skin barrier function recovering effect.

Kinesis of Intradermal Calcium Ion

Using powders in the aforementioned Table 1, kinesis of calcium ion in askin during a process of skin barrier recovery was observed.

The whole back of a hairless mouse was subjected to skin barrierdestruction treatment with acetone. 40 mg of each powder was suspendedin 200 to 400 μL of ion-exchanged water to prepare a suspension. Thesuspension was added dropwise to a 2×4 cm square of a filter paperplaced on a plastic wrap to wet it. This was applied to a back of ahairless mouse that had been subjected to the aforementioned skinbarrier destruction treatment so that the added dropwise surface wascontacted with the back, and was peeled off after 10 minutes (FIG. 2). Askin on a back of a hairless mouse was taken after 2 hours, and calciumion was visualized to confirm ion distribution.

A method of visualizing calcium ion is a method of contacting a frozentissue piece with a water-soluble gel or a plastic containing calciumgreen 1™ which can color and detect calcium ion under the constantcondition to color a calcium green 1™ and the details are described inJP-A No. 2001-324502.

In a skin after skin barrier destruction treatment, diffusion of calciumion into an epidermis occurred.

Thereafter, a skin on which the powder of Examples 1 or 2 was coated,was recovered into the normal ion localized state, while in a skincoated with the powder of any one of Examples 3 to 5, diffusion of ionwas deteriorated. From the foregoing, it was demonstrated that since theinsoluble powder of the present invention normalizes intradermal iondistribution, it exerts skin barrier function recovering effect.

Relationship Between Time Until Powder Application and Skin BarrierFunction Recovering Effect

Then, after skin barrier destruction, the relationship between time topowder application and recovery effect is investigated. 20 mg of thepowder of Example 1 in the Table 1 was suspended in 100 to 200 μL ofion-exchanged water to obtain a suspension, which was coated similarly 1hour after the aforementioned skin barrier destruction, and recoveryrate was calculated every hour. The result of comparison between notreatment after barrier destruction and the case of water coating isshown in FIG. 3.

In the case where application was performed after 1 hour passed, evenwhen the powder of Example 1 having a plate-like shape and a negativezeta-potential value was used, skin barrier function recovering effectcould not be obtained. Thereby, it was confirmed that unless a powder isapplied immediately after skin barrier destruction, the effect is notmanifested. This demonstrates that skin barrier function recoveringeffect of the insoluble powder of the present invention is closelyrelated to barrier repair mechanism that rapidly occurs in an epidermiscorneal layer after barrier destruction. In addition, it was alsoconfirmed that it is not misunderstood that since an amount of waterevaporation is reduced due to physical skin clogging by the insolublepowder, skin barrier recovery occurs.

Then, the present inventors further studied.

Zeta-Potential

In order to investigate a suitable zeta-potential regarding theinsoluble powder of the present invention, the following experiment isperformed.

According to the aforementioned method of measuring skin barrierfunction recovery rate, regarding each plate-like powder in thefollowing Table 2, a skin barrier function recovery rate was measured,and skin barrier function recovering effect was tested. TABLE 2zeta-potential Recovery Example Insoluble powder (mV) Shape effect 6Barium sulfate −2.31 plate-like ◯ 7 Barium sulfate −3.31 plate-like ◯ 8Barium sulfate −3.69 plate-like ◯ 9 Lithium doped −2.34 plate-like ◯barium sulfate 10 Sodium doped −1.71 plate-like ◯ barium sulfate 11Magnesium doped 0.41 plate-like X barium sulfate 12 Aluminum doped 3.08plate-like Δ barium sulfate

In Examples 6 to 10 in which an insoluble powder having the negativezeta-potential value was used, the result of high skin barrier functionrecovering effect was obtained. On the other hand, in Examples 11 and 12in which an insoluble powder having the positive zeta-potential valuewas used, recovering effect was not observed.

From the foregoing, it is necessary that the zeta-potential of theinsoluble powder of the present invention is a negative value.

Definition of Plate-Like

As described above, it is considered to be necessary that the insolublepowder of the present invention has a plate-like shape. Then, in orderto define “plate-like”, further, the following experiment was performedto investigate a suitable particle diameter and aspect ratio.

According to the aforementioned method of measuring skin barrierfunction recovery rate, regarding each powder in the following Table 3,a skin barrier function recovery rate was measured, and skin barrierfunction recovering effect was tested. TABLE 3 Average primary Insolubleparticle diameter aspect Recovery Example powder (μm) ratio effect 13Barium sulfate 0.05 — X 14 Barium sulfate 0.1 — X 15 Barium sulfate 0.8— Δ 16 Barium sulfate 2.0 — Δ 17 Barium sulfate 3 to 10 3 to 20 ◯ 18Barium sulfate 3 to 15 3 to 30 ◯ 19 Barium sulfate 3 to 20 3 to 40 ◯ 20Lithium doped 5 to 20 5 to 100 ◯ barium sulfate 21 Sodium doped 30 to 5030 to 250 ◯ barium sulfate

An aspect ratio expresses (average primary particle diameter)/(averagethickness).

In Examples 13 to 16 where a powder having an average primary particlediameter of smaller than 3 μm was used, even when the zeta-potential wasnegative, recovering effect was not observed, and recovery was delayedin some cases. In addition, since it is difficult to make a powderhaving a small particle diameter plate-like, an aspect ratio could notbe measured.

On the other hand, it was confirmed that in Examples 17 to 21 in which apowder having an average primary particle diameter of 3 μm or larger andan aspect ratio of 3 or more was used, recovering effect is high.

In addition, when an average primary particle diameter exceeds 100 μm,or an aspect ratio exceeds 250, usability is deteriorated in some caseswhen blended in a skin external preparation.

Thereby, it is necessary that the plate-like insoluble powders of thepresent invention have an average primary particle diameter of 3 to 100μm, and an aspect ratio of 3 to 250.

Skin Roughening Preventing and Improving Effect

Further, in order to test roughening preventing and improving effect ofthe insoluble powder of the present invention, the following experimentwas performed.

Method of Measuring Thickness of Skin

1. A hairless mouse is pre-bred for 2 days under the drying condition ofa humidity of 10% or lower and room temperature of about 25° C. Atransdermal evaporating water level (TEWL) on a back of a hairless mousewas measured with a water evaporation amount measuring apparatus(Meeco). This value is defined as a recovery rate of TEWL 100%.

2. Skin barrier destruction treatment was performed by rubbing anepidermis corneal layer on the whole back of a hairless mouse with acotton swab containing acetone until a TEWL value became 200 to 300 (2to 3 mg/cm²/hour).

3. 40 mg of each powder of Examples 13 to 19 in the Table 3 wassuspended in 200 to 400 μL of ion-exchanged water to prepare asuspension. The suspension was added dropwise to a 2×4 cm square of afilter placed on a plastic wrap to wet it. This was applied to a back ofa hairless mouse immediately after the aforementioned skin barrierdestruction so that the added dropwise surface was contacted with theback, and was peeled after 10 minutes (FIG. 2).

4. Thereafter, the mouse was bred under the aforementioned dryingcondition, a skin on a back of a hairless mouse after 48 hours wastaken, fixed in 10% formalin, embedded with paraffin, and cut into 2 μmpieces, and thickness thereof was measured with a microscope.

In addition, a hairless mouse which had not subjected to skin barrierdestruction treatment and powder coating (Control Example 1) and ahairless mouse which had been subjected to only skin barrier destructiontreatment, and had not been subjected to powder coating (ComparativeExample 1) were placed under the similar drying and, thereafter,thickness of a skin was measured. When thickness of a skin wasincreased, it was determined that epidermis proliferating propertyabnormality occurred and skin roughening occurred.

Results are shown in FIG. 4.

It was confirmed that in Examples 17 to 19, as compared with ComparativeExample 1 in which a powder is not coated, epidermis proliferatingproperty abnormality is remarkably prevented, and this is approximatelyequivalent to Control Example 1 in which skin barrier destruction is notperformed. On the other hand, in Examples 13 to 16, epidermisproliferating property abnormality was not prevented at all.

In addition, as compared with Comparative Example 1, it was observedwith naked eyes that skin roughening was further exacerbated in Examples13 to 16, while it was observed that skin roughening was suppressed inExamples 17 to 19. Thereby, it was confirmed that the insoluble powderhaving an average primary particle diameter of 3 to 100 μm, an aspectratio of 3 to 250, and the zeta-potential being a negative value hasexcellent skin roughening preventing and improving effect.

Skin Barrier Function Recovering Effect of Skin External Preparation(Mouse Test)

Then, using a foundation in which the insoluble powder of the presentinvention was blended, skin barrier function recovering effect wastested.

According to the aforementioned method of measuring a skin barrierfunction recovery rate, regarding each powdery foundation of theformulation shown in the following Table 4, a skin barrier functionrecovery rate was calculated, and this was compared with a hairlessmouse which had not been subjected to treatment after skin barrierdestruction. It can be said that as a recovery rate, in particular, arecovery rate at an early time zone is better, skin barrier functionrecovering effect is higher.

Results are shown in FIG. 5 (n=9). TABLE 4 Blending example 1 2 3Insoluble powder of Example 7 12 8 0 Metal soap treated talc 18.52 14.5210.52 (TALK ACS-515 ™) Silicone treated mica (SNP-WEY-(S) ™) 15 15 15Silicone treated sericite (SNH-300ST ™) 22 22 22 Silicone treatedsynthesis mica 4 4 4 (SNH-ST(EF) ™) Silicone treated titanium oxide 6 66 (SNH-R-KB-1 ™) Spherical PMMA powder 6 6 6 (MICROSFER M-330 ™)Spherical PMMA covering mica 7 7 7 (COMPOSITE M-P ™) Silicone treatedfine particle 4 4 4 titanium oxide (TITANIUM OXIDE MT-020 ™) Siliconetreated iron oxide + Silicone 1.34 1.34 1.34 treated talc (SNP-R-1(N) ™)Silicone treated iron oxide + Silicone 3.32 3.32 3.32 treated talc(SNP-Y-75(N) ™) Silicone treated iron oxide + Silicone 0.4 0.4 0.4treated talc (SNP-BL-1(N) ™) Ethyl paraben 0.4 0.4 0.4Dimethylsilicone(SILICONE KF-96A-6 ™) 5 5 5 Glycerol trioctanoate(RA-G-308 ™) 3 3 3 Octyl methoxy cinnamate 3 3 3 Sorbitansesuquiisostearate 1 1 1 (ESTEMOL 182 ™) Vitamin E (E-mix D ™) 0.02 0.020.02 100 100 100

In a mouse coated with Blending example 2 containing 8% by weight of theinsoluble powder of the present invention or Blending example 1containing 12% by weight of the powder, a recovery rate of TEWL washigher as compared with non-treated mouse. In addition, as a content ofa powder was higher, a recovery rate was higher. However, in a mousecoated with Blending example 3 not containing the insoluble powder ofthe present invention, a recovery rate was deteriorated as compared witha non-treated mouse. Therefore, it was confirmed that a skin externalpreparation containing the insoluble powder of the present invention hasskin barrier function recovering effect, and it is suggested that apreferable content of the insoluble powder in a skin externalpreparation is 1 to 30% by weight, in particular 8 to 30% by weight.

Skin Barrier Function Recovering Effect of Skin External Preparation(Human Test)

Then, using a foundation in which the insoluble powder of the presentinvention is blended, skin barrier function recovering effect to a humanwas tested.

Two kinds of foundations of two utilities having the formulations shownin Table were prepared, and were continuously coated on a human face for8 hours or longer in the daytime for 2 weeks. A transdermal evaporatingwater level (TEWL) on a human face was measured with a water evaporationamount measuring apparatus (Meeco) before sample application and aftercontinuous application for 2 weeks, and this was compared with the caseof non-treatment. It can be said that as a TEWL value is lower, skinbarrier function is recovered. Results are shown in FIG. 6 (n=9). TABLE5 Blending example 4 5 (1)Metal soap treated talc residue residue(2)Silicone treated talc 1.5 1.5 (3)Silicone treated mica 8 8(4)Silicone treated sericite 30 30 (5)Silicone treated synthesis mica 44 (6)Insoluble powder of Example 7 15 0 (7)Silicone treated titaniumoxide 8 8 (8)Silicone treated iron oxide 2.7 2.7 (9)Spherical alkylpolyacrylate 6 6 resin powder (10)Spherical alkyl polyacrylate 7 7 resinfine powder coating mica (11)Dimethylpolysiloxane 5 5 (12)Glyceroltriisooctanoate 3 3 (13)2-Ethylhexyl para-methoxy- 3 3 cinnamate(14)Sorbitan sesuquiisostearate 1 1 (15)Antiseptics proper quantityproper quantity (16)Antixidant proper quantity proper quantity(17)Perfume proper quantity proper quantity

Ingredients (1) to (10) were mixed and ground, and heated and melted(11) to (17) were added thereto to stir and mix them, followed byfurther grinding treatment, which was molded under a pressure.

When Blending example 5 in which the insoluble powder of the presentinvention is not blended was coated, improvement in TEWL value is notobserved, while when Blending example 4 in which 15% by weight of theinsoluble powder of the present invention is blended was coated, a TEWLvalue was dramatically decreased from about 120 to about 60, and it wasseen that skin barrier function was improved.

Therefore, it was confirmed that the insoluble powder of the presentinvention has skin barrier function recovering effect also in a human.

Then, in order to compare skin barrier function recovering effectbetween metal-doped type barium sulfate and barium sulfate not dopedwith a metal (Comparative example 2) in Table 6, the followingexperiment was performed. A skin barrier function recovery rate wascalculated as described above. Results are shown in FIGS. 7 to 13. TABLE6 Doping Content Kinds of insoluble powders element by % Example 22 Zndoped barium sulfate Zinc 0.170% Example 23 Na doped barium sulfateSodium 0.013% Example 24 Li doped barium sulfate Lithium <0.001%  Example 25 Ca doped barium sulfate Calcium 0.074% Example 26 Al dopedbarium sulfate Aluminum 0.004% Example 27 Mg doped barium sulfateMagnesium 0.003% Example 28 Fe doped barium sulfate Iron 0.200%Comparative 2 Barium sulfate — —

It was confirmed that, in the case where a powder of barium sulfatedoped with Zn, Na or Li is used (Examples 22 to 24), skin barrierrecovery is promoted as compared with the case where a powder ofnon-doped barium sulfate is used (Comparative example 2). In addition,in the case where a powder of barium sulfate doped with Ca or Al is used(Examples 25 and 26), there was no influence on skin barrier recovery.On the other hand, in the case where a powder of barium sulfate dopedwith Mg or Fe is used (Examples 27 and 28), it was confirmed that skinbarrier recovery was conversely delayed.

Thereby, it was confirmed that a powder of barium sulfate doped with Zn,Li or Na has specifically excellent skin roughening improving effect ascompared with barium sulfate not doped with a metal.

Skin Roughening Preventing and Improving Effect

The thickness of a skin of a hairless mouse receiving no damage wasmeasured (Control example 2).

The whole back of a hairless mouse under drying was repeatedly wipedwith acetone, giving damage.

20 mg of each powder of barium sulfate doped with a metal shown inExamples 22 and 28 in Table 6 was suspended in 100 to 200 μL ofion-exchanged water to prepare a suspension. The suspension was addeddropwise to a 2 cm square of a filter placed on a plastic wrap to wetit. This was coated on a back of a hairless mouse after theaforementioned skin barrier destruction treatment for 10 minutes so thatthe added dropwise surface was contacted with the back, and peeled.

This was placed as it was under drying, thickness of a skin on a back ofa hairless mouse after 2 days was measured, and was compared withthickness of a skin of a place not coated with a sample. When thicknessof a skin is increased, it is determined that epidermis proliferatingproperty abnormality occurred, and skin roughening occurred. Results areshown in FIG. 14.

It was confirmed that, at a place using a powder of barium sulfate dopedwith Fe of Example 28, epidermis proliferating property abnormalityfurther progressed as compared with a place not coated with a sample(Comparative example 4), while at a place using a powder of bariumsulfate doped with Zn of Example 22, epidermis proliferating propertyabnormality is prevented as compared with a place not coated with asample (Comparative example 3). In addition, on appearance, falling wasremarkably observed in Example 28, while no falling was recognized inExample 22. Thereby, it was confirmed that a powder of barium sulfatedoped with Zn has excellent skin roughening preventing and improvingeffect. Embodiment 1 Barium sulfate Average primary particle diameter: 3to 10 μm Aspect ratio: 3 to 20 Zeta-potential: −2.31(Preparation Process)

500 mL of 80 mmol/L/aqueous barium chloride solution and 1000 mL ofion-exchanged water were stirred to mix in a 300 mL round bottomseparable flask. After the liquid temperature was adjusted to 100° C.,500 mL of 80 mmol/L-aqueous sodium sulfate solution was added dropwisewith stirring. Immediately, white barium sulfate was produced andprecipitated, and the reaction solution became the suspended state.After addition of an aqueous solution of sodium sulfate, a reaction wascarried out for 1 hour. After completion of the reaction, the reactionsolution was cooled to room temperature, the resulting solid product wasprecipitated, filtered and washed with water to remove a salt, followedby drying at 120° C. for 12 hours. Then, the solid product was subjectedto grinding treatment (grinding treatment was carried out for 5 minutesusing a small size-grinding machine) to obtain a white powder.

According to the aforementioned method of measuring skin barrierfunction recovery rate, a skin barrier function recovery rate wasmeasured, and the results are shown in FIG. 15. Embodiment 2 Bariumsulfate Average primary particle diameter: 3-15 μm, Aspect ratio: 3-30,Zeta-potential: −3.31(Preparation Process)

500 mL of 60 mmol/L/aqueous barium chloride solution and 1000 mL ofion-exchanged water were stirred to mix in a 300 mL round bottomseparable flask. After the liquid temperature was adjusted to 100° C.,500 mL of 60 mmol/L-aqueous sodium sulfate solution was added dropwisewith stirring. Immediately, white barium sulfate was produced andprecipitated, and the reaction solution became the suspended state.After addition of an aqueous solution of sodium sulfate, a reaction wascarried out for 1 hour. After completion of the reaction, the reactionsolution was cooled to room temperature, the resulting solid product wasprecipitated, filtered and washed with water to remove a salt, followedby drying at 120° C. for 12 hours. Then, the solid product was subjectedto grinding treatment (grinding treatment was carried out for 5 minutesusing a small size-grinding machine) to obtain a white powder.

According to the aforementioned method of measuring skin barrierfunction recovery rate, a skin barrier function recovery rate wasmeasured, and the results are shown in FIG. 16. Embodiment 3 Bariumsulfate Average primary particle diameter: 3-20 μm, Aspect ratio: 3-40,Zeta-potential: −3.69(Preparation Process)

500 mL of 40 mmol/L/aqueous barium chloride solution and 1000 mL ofion-exchanged water were stirred to mix in a 300 mL round bottomseparable flask. After the liquid temperature was adjusted to 100° C.,500 mL of 40 mmol/L-aqueous sodium sulfate solution was added dropwisewith stirring. Immediately, white barium sulfate was produced andprecipitated, and the reaction solution became the suspended state.After addition of an aqueous solution of sodium sulfate, a reaction wascarried out for 1 hour. After completion of the reaction, the reactionsolution was cooled to room temperature, the resulting solid product wasprecipitated, filtered and washed with water to remove a salt, followedby drying at 120° C. for 12 hours. Then, the solid product was subjectedto grinding treatment (grinding treatment was carried out for 5 minutesusing a small size-grinding machine) to obtain a white powder.

According to the aforementioned method of measuring skin barrierfunction recovery rate, a skin barrier function recovery rate wasmeasured, and the results are shown in FIG. 17. Embodiment 4 Lithiumdope barium sulfate Average primary particle diameter: 5-20 μm, Aspectratio: 5-100, Zeta-potential: −2.34(Preparation Process)

500 mL of 60 mmol/L/aqueous barium chloride solution, 500 mL of 60mmol/L/aqueous lithium chloride solution and 1000 mL of ion-exchangedwater were stirred to mix in a 300 mL round bottom separable flask.After the liquid temperature was adjusted to 100° C., 500 mL of 60mmol/L-aqueous sodium sulfate solution was added dropwise with stirring.Immediately, white barium sulfate was produced and precipitated, and thereaction solution became the suspended state. After addition of anaqueous solution of sodium sulfate, a reaction was carried out for 1hour. After completion of the reaction, the reaction solution was cooledto room temperature, the resulting solid product was precipitated,filtered and washed with water to remove a salt, followed by drying at120° C. for 12 hours. Then, the solid product was subjected to grindingtreatment (grinding treatment was carried out for 5 minutes using asmall size-grinding machine) to obtain a white powder.

According to the aforementioned method of measuring skin barrierfunction recovery rate, a skin barrier function recovery rate wasmeasured, and the results are shown in FIG. 18. Embodiment 5 Sodium dopebarium sulfate Average primary particle diameter: 30-50 μm, Aspectratio: 30-250, Zeta-potential: −1.71(Preparation Process)

500 mL of 60 mmol/L/aqueous barium chloride solution, 500 mL of 60mmol/L/aqueous sodium chloride solution and 1000 mL of ion-exchangedwater were stirred to mix in a 300 mL round bottom separable flask.After the liquid temperature was adjusted to 100° C., 500 mL of 60mmol/L-aqueous sodium sulfate solution was added dropwise with stirring.Immediately, white barium sulfate was produced and precipitated, and thereaction solution became the suspended state. After addition of anaqueous solution of sodium sulfate, a reaction was carried out for 1hour. After completion of the reaction, the reaction solution was cooledto room temperature, the resulting solid product was precipitated,filtered and washed with water to remove a salt, followed by drying at120° C. for 12 hours. Then, the solid product was subjected to grindingtreatment (grinding treatment was carried out for 5 minutes using asmall size-grinding machine) to obtain a white powder.

According to the aforementioned method of measuring skin barrierfunction recovery rate, a skin barrier function recovery rate wasmeasured, and the results are shown in FIG. 19.

Embodiment 6 Zinc Dope Barium Sulfate

(Preparation Process)

500 mL of 0.06 mol/L/aqueous barium chloride solution, 500 mL of 0.06mol/L/aqueous zinc chloride solution and 1 L of ion-exchanged water werestirred to mix in a 3 L round bottom separable flask. After the liquidtemperature was adjusted to 100° C., 500 mL of 0.06 mol/L-aqueous sodiumsulfate solution was added dropwise with stirring. Immediately, whitebarium sulfate was produced and precipitated, and the reaction solutionbecame the suspended state. After addition of an aqueous solution ofsodium sulfate, a reaction was carried out for 1 hour. After completionof the reaction, the reaction solution was cooled to room temperature,the resulting solid product was precipitated, filtered and washed withwater to remove a salt, followed by drying at 120° C. for 12 hours.

According to the aforementioned method of measuring skin barrierfunction recovery rate, a skin barrier function recovery rate wasmeasured, and the results are shown in FIG. 20. Embodiment 7 Solidpowdery foundation (prescription) Wt % (1) Silicone treated sericite 15(2) Silicone treated mica 20 (3) Silicone treated synthesis mica 10 (4)Silicone treated talc remainder (5) Network type silicone resin coveringorgano 3 polysiloxane elastomer spherical powder (6) Methyl siloxanenetwork polymer spherical powder 4 (7) Barium sulfate 10 (Averageprimary particle size: 10 μm, aspect ratio: 10, zeta-potential: −0.3 mV)(8) Zinc myristate 2 (9) Powdery hydrocarbon wax 3 (10) Silicone treatedtitanium oxide 10 (11) Silicone treated iron oxide 4 (12) Siliconetreated zinc oxide 5 (13) Squalane 3 (14) Dimethylpolysiloxane 4 (15)Paramethoxy cinnamate 2-ethylhexyl 3 (16) Polyoxyethylene polyalkylmodified silicone 1 (17) Sorbitan sesqui isostearate 1 (18) Antisepticsproper quantity (19) Anti oxidant proper quantity (20) Perfume properquantity

(Process)

Respective ingredients of 1 to 12 were mixed and ground, respectiveingredients of 13 to 20 were added to mix thereto with stirring and mixthem, this was further ground, and was molded in a container to obtain asolid powdery foundation. Embodiment 8 Baby powder (prescription) wt %(1) Talc remainder (2) Synthesis mica 12 (3) Magnesium stearate 4 (4)Zinc white 3 (5) Barium sulfate 20 (Average primary particle size: 20μm, aspect ratio: 40, zeta-potential: −3.7 mV) (6) Perfume properquantity

(Process)

Respective ingredients 1 to 5 were stirred to mix, 6 was sprayedthereto, and this was mixed and subjected to grinding treatment toobtain a baby powder. Embodiment 9 White powder (prescription) wt % (1)Talc remainder (2) Mica 12 (3) Sericite 8 (4) Spherical methyl siloxanenetwork polymer powder 3 (5) Boron nitride 4 (6) Barium sulfate 40(Average primary particle size: 20 μm, aspect ratio: 40, zeta-potential:−3.7 mV) (7) Iron oxide 2 (8) Ultramarineblue covering mica titanium 1(9) N-acylated lysine 2 (10) Zinc myristate 3 (11) Powdery synthesispolyethylene wax 1 (12) Gycerin triisooctanoate 3 (13) Liquid paraffin 2(14) Sorbitan sesqui isostearate 0.5 (15) Antiseptics proper quantity(16) Perfume proper quantity

(Process)

Respective ingredients of 1 to 11 were stirred to mix, uniformly mixed12 to 16 were added thereto to mix and grind them, and this was moldedinto an intermediate dish to obtain a white powder. Embodiment 10 O/Wtype emulsion cosmetic (prescription) Wt % (1) Purified water remainder(2) Propylene glycol 4 (3) Glycerol 2 (4) Sodium methaphosphate properquantity (5) Bentonite 2 (6) Potassium hydroxide 0.4 (7) Palmitic acid1.2 (8) Isostearic acid 1 (9) Titanium oxide 10 (10) Iron oxide properquantity (11) Spherical silica powder 5 (12) Barium sulfate 8 (Averageprimary particle size: 20 μm, aspect ratio: 7, zeta-potential: −0.3 mV)(13) Talc 4 (14) Mica 2 (15) Mica titanium 1 (16) Glycerin monostearate1 (17) Polyoxyethylene sorbitan monostearate 0.5 (18) Cetyl alcohol 0.4(19) Batyl alcohol 0.5 (20) Liquid paraffin 5 (21) Dimethylpolysiloxane5 (22) Paramethoxy cinnamate acid 2-ethylhexyl 3 (23) Vaseline 1 (24)Antiseptics proper quantity (25) Perfume proper quantity

(Process)

1 to 5 were uniformly stirred to mix, 6 to 8 were added thereto to mixthem, and mixed and ground 9 to 15 were added thereto to disperse them.To this were added heated and melted 16 to 25, and this was uniformlyemulsified to obtain an oil in water-type emulsion cosmetic. Embodiment11 W/O type emulsion cosmetic (prescription) Wt % (1) Sphericalpolyurethane powder 3 (2) Silicone treated mica titanium 2 (3) Bariumsulfate 4 (Average primary particle size: 30 μm, aspect ratio: 15,zeta-potential: −1.7 mV) (4) Silicone treated titanium oxide 10 (5)Silicone treated iron oxide 4 (6) Silicone treated talc 2 (7) Siliconetreated baking mica 3 (8) Purified water remainder (9) Dipropyleneglycol 8 (10) Decamethyl cyclopenta siloxane 25 (11) Dodevamethylcyclohexa siloxane 15 (12) Dimethylpolysiloxane 3 (13) Silicone resin 2(14) Polyether modified silicone 1.5 (15) Alkyl polyether modifiedsilicone 0.5 (16) Isostearic acid 1 (17) Antioxidant proper quantity(18) Antiseptics proper quantity

(Process)

Respective ingredients 10 to 18 were uniformly mixed, mixed and groundrespective ingredients 1 to 7 were added thereto to disperse them. Then,uniformly mixed and melted 8 to 9 were added to emulsify them, which wascharged into a container to obtain a water in oil type emulsioncosmetic. Embodiment 12 Eyes shadow (prescription) Wt % (1) Talcremainder (2) Sericite 7 (3) Mica 15 (4) Spherical polymethylmethacrylate powder 3 (5) Spherical styrene resin covering synthesismica 2 (6) Iron oxide covering mica titanium 4 (7) Iron oxide 1.5 (8)Barium sulfate 10 (Average primary particle size: 20 μm, aspect ratio:15, zeta-potential: −2.4 mV) (9) Squalane 2 (10) Dimethylpolysiloxane 2(11) Sorbitan monooleate 0.5 (12) Antiseptics proper quantity (13)Perfume proper quantity

(Process)

Respective ingredients 1 to 8 were mixed and ground, mixed respectiveingredients of 9 to 13 were added thereto to stir and mix them, and thiswas molded into an intermediate dish to obtain an eyes shadow.Embodiment 13 Oily stick (prescription) Wt % (1) Carnauba wax 1 (2)Candelilla wax 2 (3) Ceresin 10 (4) Squalane remainder (5) Glycerintriisooctanoate 9 (6) Glycerin diisostearate 13 (7) Dimethylpolysiloxane5 (Viscosity: 90,000 mPa · s at 25° C.) (8) Dimethylpolysiloxane 5(Viscosity: 1,000 mPa · s at 25° C.) (9) Silicone resin 8 (10) Hydroxypropyl-beta-cyclodextrin 1 (11) Macademian nut oil fatty acidcholesteryl 3.5 (12) Synthesis sodium silicate magnesium 0.5 (13)Hydrophobic silica 0.5 (14) Purified water 2 (15) Spherical siliconeresin powder coating mica 3 (16) Spherical nylon powder 4 (17) Bariumsulfate 10 (Average primary particle size: 40 μm, aspect ratio: 10,zeta-potential: −1.7 mV) (18) Coloring material proper quantity (19)Antiseptics proper quantity (20) Perfume proper quantity

(Process)

12 to 13 were dispersed into 11 heated to 60° C., and uniformly melted10 and 14 were added thereto to sufficiently stir them. This was addedto separately heated and melted 1 to 9 to sufficiently stir them, 15 to20 were further added to disperse and stir them and, thereafter, thiswas charged into a container to obtain an oily stick. Embodiment 14Powdery foundation (prescription) Wt % Sericite 8 Synthesis mica 5 Talctoo 100 Silica covering zinc oxide 5 Zinc-dope barium sulfate 22Spherical nylon powder 5 Spherical silicone elastic powder 15 Titaniumoxide 12 Ferric oxide 0.8 Yellow iron oxide 2 Black iron oxide 0.1Dimethylpolysiloxane 3 Liquid paraffin 5 Vaseline 5 Sorbitan sesquiisostearate 1 Paraben proper quantity Anti-Oxidant proper quantityPerfume proper quantity

(Process)

The aforementioned all ingredients were ground and mixed with a beadmedium mill for a constant time in an alcohol, the resulting slurry wascharged into an intermediate dish container, and pressed while analcohol was sucked, to prepare a powdery foundation. Embodiment 15Powdery foundation (prescription) Wt % Mica 23 Baking sericite 15Lecithin treated zinc-dope barium sulfate 10 Zinc-dope talc too 100Spherical silicone powder 5 Spherical silicone elastic powder 10Titanium oxide 12 Ferric oxide 0.8 Yellow iron oxide 2 Black iron oxide0.1 Dimethylpolysiloxane 4 Liquid paraffin 6 Vaseline 5 Sorbitan sesquiisostearate 1 Paraben proper quantity Oxidation inhibitor properquantity Perfume proper quantity

(Process)

The aforementioned all ingredients were ground and mixed with a beadmedium mill for a constant time in an alcohol, the resulting slurry wascharged into an intermediate dish container, and pressed while analcohol was sucked, to prepare a powdery foundation. Embodiment 16Powdery foundation (prescription) wt % Silicone treated sericite 18Silicone treated synthesis mica 12 Silicone treated talc too 100Silicone treated lithium-dope barium sulfate 10 Spherical polymethylmethacrylate resin powder 5 Spherical silicone elastic powder 2Spherical polyurethane elastic powder 3 Aluminum stearate treated fineparticle titanium oxide 6 Silica covering zinc oxide 4 Silicone treatedtitanium oxide 10 Silicone treated ferric oxide 1.2 Silicone treatedyellow iron oxide 2.5 Silicone treated black iron oxide 0.9 Parabenproper quantity Dimethylpolysiloxane 4 Methyl phenyl polysiloxane 3Octhyl methoxy Cinnamate 3 Polyether silicone 2 Anti-oxidant properquantity Perfume proper quantity

(Process)

The aforementioned powder all ingredients were mixed with a Henschelmixer, a total mixture of oily phase ingredients warmed to 80° C. wasadded using a spraying nozzle, and this was stirred to mix for 10minutes. Thereafter, the material was allowed to stand to cool to 40°C., taken out, and ground with a grinding machine twice to prepare apowdery foundation. Embodiment 17 Powdery foundation (prescription) wt %Fluorine modified silicone treated synthesis mica too 100 Fluorinemodified silicone treated talc 13 Fluorine modified silicone treatedsodium-dope 15 barium sulfate Spherical nylon powder 7 Sphericalsilicone elastic powder 2 Spherical polyurethane elastic powder 1Fluorine modified silicone treated fine particle 10 titanium oxideSilicone treated titanium oxide 9 Silicone treated ferric oxide 1.4Silicone treated yellow iron oxide 2.8 Silicone treated black iron oxide1.0 Silica covering zinc oxide 5 Paraben proper quantityDimethylpolysiloxane 4 methyl phenyl polysiloxane 1 Octhyl methoxyCinnamate 3 Polyether silicone 2 Vaseline 1 Anti-oxidant proper quantityPerfume proper quantity

(Process)

The aforementioned powder all ingredients were mixed with a Henschelmixer, a total mixture of oily phase ingredients warmed to 80° C. wasadded using a spraying nozzle, and this was stirred to mix for 10minutes. Thereafter, the material was allowed to stand to cool to 40°C., taken out, and ground with a grinding machine two times to prepare apowdery foundation. Embodiment 18 Face powder (White powder)(prescription) wt % Zinc-dope barium sulfate 35 Porous plate-like silica5 Metal soap treated talc too 100 Boron nitride 7 Silica covering zincoxide 3 Ferric oxide 0.3 Yellow iron oxide 1.2 Spherical silicone powder5 Vaseline 1 Squalane 2 Ester oil 1 Dimethylpolysiloxane 1 Parabenproper quantity Anti-oxidant proper quantity Perfume proper quantity

(Process)

The aforementioned powder all ingredients were mixed with a Henschelmixer, a total mixture of oily phase ingredients warmed to 80° C. wasadded using a spraying nozzle, and this was stirred to mix for 5minutes. Thereafter, the material was allowed to stand to cool to 40°C., taken out, and ground with a grinding machine two times to prepare aface powder. Embodiment 19 Loose powder (powdery white powder)(prescription) Wt % Talc too 100 Synthesis mica 10 Zinc-dope bariumsulfate 25 Spherical porous silica powder 5 Spherical alumina powder 5Zinc white 3 Silica covering zinc oxide 5 Squalane 3 Paraben properquantity Perfume proper quantity

(Process)

The aforementioned powder all ingredients were mixed with a Henschelmixer, a total mixture of oily phase ingredients warmed to 80° C. wasadded using a spraying nozzle, and this was stirred to mix for 5minutes. Thereafter, the material was allowed to stand to cool to 40°C., taken out, and ground with a grinding machine two times to prepare aloose powder. Embodiment 20 O/W type emulsified cream foundation(prescription) Wt % Sericite 7 Silicic acid anhydride covering zincoxide 8 Zinc-dope barium sulfate 20 Ferric oxide 0.3 Yellow iron oxide1.2 Black iron oxide 0.6 Spherical polyethylene powder 6 Squalane 10Olive oil 10 Stearic acid 2 Glycerin monostearate 2 Sorbitan POE (40)monostearate 2 Glycerol 5 Triethanolamine 0.8 pH modifier properquantity Antiseptics proper quantity Ion exchanged water too 100

(Process)

A powder was dispersed in water phase ingredients, and separately warmedoily phase ingredients were added to emulsify them at 85° C. Atcompletion of emulsification, the material was cooled to roomtemperature, and charged into a container to obtain a cream foundation.Embodiment 21 O/W type emulsified makeup foundation (prescription) Wt %Glycerol 20 Pentane 1,2-diol 3 1,3-butylene glycol 1 Liquid paraffin 7.5Isostearic acid 0.5 Medicine 0.3 Di 2-ethylhexyl phthalate 0.3 Sphericalsilica 4 Zinc-dope barium sulfate 5 Stabilizer proper quantity Perfumeproper quantity Ion exchanged water too 100

(Process)

A powder was dispersed in water phase ingredients, and separately warmedoily phase ingredients were added to emulsify them at 85° C. Atcompletion of emulsification, the material was cooled to roomtemperature, and charged into a container to obtain a cream foundation.Embodiment 22 W/O type emulsified liquid foundation (prescription) Wt %Silicone treated zinc-dope barium sulfate 15 Silicone treated titaniumoxide 8 Silicone treated ferric oxide 1.2 Silicone treated yellow ironoxide 2.6 Silicone treated black iron oxide 0.6 Spherical siliconeelastic powder 2 Spherical polymethyl methacrylate powder 5 Octyl silanetreated fine particle titanium oxide 6 Cyclomethylsilicone too 100Dimethylpolysiloxane 4 Squalane 3 Polyether modified silicone 2 Sorbitansesqui isostearate 1 Dispersant proper quantity Dipropylene glycol 2 Ionexchange water 20 Paraben proper quantity Anti-oxidant proper quantityPerfume proper quantity

(Process)

All oil phase ingredients were warmed to 85° C. dissolved and dispersed,and separately warmed water phase ingredients were added to emulsifythem at 85° C. At completion of emulsification, the material was cooledto room temperature, and charged into a container to obtain a liquidfoundation. Embodiment 23 W/O type emulsified liquid foundation(prescription) Wt % Fluorine modified silicone treated mica 5 Fluorinemodified silicone treated sericite 7 Fluorine modified silicone treatedtitanium oxide 12 Fluorine modified silicone treated iron oxide 4Fluorine modified silicone treated zinc-dope 6 barium sulfateOctylsilane treated fine particle titanium oxide 4 Spherical polymethylmethacrylate powder 5 Spherical silicone elastic powder 5 Silicacovering zinc oxide 4 Cyclomethylsilicone too 100 Dimethylpolysiloxane 4Squalane 3 Polyether modified silicone 1 Fluorine modified polyethermodified silicone 3 Dispersion auxiliary proper quantity Dipropyleneglycol 2 Ion exchanged water 20 Paraben proper quantity Antioxidantproper quantity Perfume proper quantity

(Process)

All oil phase ingredients were warmed to 85° C. dissolved and dispersed,and separately warmed water phase ingredients were added to emulsifythem at 85° C. At completion of emulsification, the material was cooledto room temperature, and charged into a container to obtain a liquidfoundation. Embodiment 24 Oily eyes shadow (prescription) Wt %Dimethylsilicone 10 Ester oil 10 Liquid paraffin too 100 Squalane 10Sorbitan sesqi isostearate 1 Polyethylene wax 8 Ceresin wax 3 Mica 7Spherical cellulose powder (about 6 μm) 5 Zinc-dope barium sulfate 25Anti-oxidant proper quantity Perfume proper quantity

(Process)

A mixture of an oily phase and powdery ingredients was warmed to 85° C.to melt and disperse it, and this was degassed, and charged into anintermediate dish to prepare an oily eyes shadow. Embodiment 25 Lipstick(prescription) Wt % Octhyl methoxy cinnamate 5 Polyethylene wax 10Ceresin wax 3 Lanolin 20 Polybutene 20 Dimethylsilicone 12 Ester oil too100 Titanium oxide 4.5 Red 201 0.5 Red 202 1.1 Red 223 0.3 Sphericalpolyethylene powder (about 5 μm) 2 Zinc-dope barium sulfate 5 Redinterference pearl agent 5 Antioxidant proper quantity Perfume properquantity

(Process)

A mixture of an oily phase and powdery ingredients was warmed to 85° C.to melt and disperse it, and this was degassed, and charged into an moldto prepare an lip stick.

Using the insoluble powder of the present invention, the skin barrierfunction recovering powder with excellent skin roughenig preventing andimproving effect and skin external composition can be obtained.

1. An insoluble powder characterized in that the zeta-potential isnegative value, and a main ingredient is barium sulfate.
 2. An insolublepowder characterized in that the zeta-potential is negative value, and amain ingredient is metal doped barium sulfate.
 3. The insoluble powderaccording to claim 1, wherein an average primary particle diameter is 3to 100 μm and an aspect ratio is 3 to
 250. 4. The insoluble powderaccording to claim 2, wherein said powder is a metal dope barium sulfatepowder obtained by reacting a barium ion and a sulfate ion in thepresence of a metal ion.
 5. The insoluble powder according to claim 4,wherein a mole ratio of the barium ion, the sulfate ion and the metalion is 1:0.5 to 2:0.001 to
 10. 6. The insoluble powder according toclaim 4, wherein said the metal ion is one or more selected from thegroup consisting of a lithium ion, a sodium ion and a zinc ion.
 7. Askin barrier function recovering powder comprising of the powderaccording to claim
 1. 8. A skin roughening preventing and improvingpowder comprising of the powder according to claim
 1. 9. A skin externalcomposition characterized in that a content of the powder according toclaim 1 is 1 to 40% by weight.
 10. An use of the powder according toclaim 1 as a skin barrier function recovering agent.
 11. An use of thepowder according to claim 1 as a skin roughening preventing andimproving agent.
 12. The insoluble powder according to claim 2, whereinan average primary particle diameter is 3 to 100 μm and an aspect ratiois 3 to
 250. 13. A skin barrier function recovering powder comprising ofthe powder according to claim
 2. 14. A skin roughening preventing andimproving powder comprising of the powder according to claim
 2. 15. Askin external composition characterized in that a content of the powderaccording to claim 2 is 1 to 40% by weight.
 16. An use of the powderaccording to claim 2 as a skin barrier function recovering agent.
 17. Anuse of the powder according to claim 2 as a skin roughening preventingand improving agent.